It is the long range purpose of this project to examine collagen biosynthesis and aspects of the control of that synthesis; collagen messenger RNA is being extracted from a number of connective tissues including rat calvaria and chondrosarcoma is being translated in several cell-free protein synthesizing systems. A search has also been made for collagen-specific tRNAs, initiation factors and other materials which modulate in vitro synthesis. Rates of messenger RNA labeling in intact cells, and coordination of message formation with production of extracellular matrix, are being examined also in an attempt to obtain in vitro tissue culture models of regulation mechanisms for collagen production. Cells in tissue culture from patients with known defects in collagen production such as osteogenesis imperfecta and Ehlers-Danlos syndrome are being surveyed for lesions in the translational apparatus.